feat: add Obsidian CLI API service

- Add Docker image for the official Obsidian desktop app and CLI.

- Start Obsidian headlessly with Xvfb and DBus setup.

- Expose a safe structured HTTP command API without shell execution.

- Add JWT-based vault, path, and command authorization.

- Support single-vault and multi-vault container mounts.

- Add TypeScript SDK helpers for Obsidian CLI commands.

- Add n8n community node package with Obsidian operations.

- Add docs, compose config, tests, and production image workflow.

app/config.py

@@ -0,0 +1,37 @@
+from pathlib import Path
+import json, os
+
+JWT_SECRET = os.getenv("OBSIDIAN_JWT_SECRET", "")
+DEFAULT_TIMEOUT = float(os.getenv("COMMAND_TIMEOUT", "60"))
+MAX_TIMEOUT = float(os.getenv("MAX_COMMAND_TIMEOUT", "300"))
+CLI_BIN = os.getenv("OBSIDIAN_CLI_BIN", "obsidian")
+VAULT_PATH = Path(os.getenv("OBSIDIAN_VAULT_PATH", "/vault")).resolve()
+HOST = os.getenv("OBSIDIAN_API_HOST", "0.0.0.0")
+PORT = int(os.getenv("OBSIDIAN_API_PORT", "8080"))
+
+def parse_registered_vaults() -> dict[str, str]:
+  raw = os.getenv("OBSIDIAN_VAULTS", "").strip()
+  vaults:dict[str, str] = {}
+
+  if raw:
+    try:
+      parsed = json.loads(raw)
+      if isinstance(parsed, dict):
+        return {str(name): str(path) for name, path in parsed.items()}
+    except json.JSONDecodeError:
+      pass
+
+    for chunk in raw.replace("\n", ",").split(","):
+      chunk = chunk.strip()
+      if not chunk or "=" not in chunk:
+        continue
+      name, path = chunk.split("=", 1)
+      vaults[name.strip()] = path.strip()
+
+  if not vaults:
+    vaults[VAULT_PATH.name or "vault"] = str(VAULT_PATH)
+
+  return vaults
+
+REGISTERED_VAULTS = parse_registered_vaults()
+DEFAULT_VAULT_NAME = next(iter(REGISTERED_VAULTS), VAULT_PATH.name or "vault")